By Jean L. Bolognia, MD, Professor of Dermatology, Department of Dermatology, Yale University, New Haven, CT, USA; Joseph L. Jorizzo, MD, Professor and Former(Founding) Chair, Department of Dermatology, Wake Forest University, Winston-Salem, NC; and Ronald P. Rapini, MD, Professor and Chair, Department of Dermatology, Professor of Pathology, University of Texas Medical School and MD Anderson Cancer Center, Professor of Pathology, Houston, TX |